Years ago, Bose virtually created the active noise-canceling headphone business with its QuietComfort headphones, aggressively marketed towards travelers -- people who would be willing to tote around a pair of earcups in order to screen out ambient noise, rendering their music or audiobooks clearer without having to turn up the volume to dangerous levels. A subsequent release, QuietComfort 2, started out impressive and went through underpublicized evolutions during its extended life span, with sonic and small cosmetic tweaks designed to help the $300 headset remain relevant as much less expensive competitors emerged. Then Bose misfired with QuietComfort 3 ("QC3"), an even more expensive "on-ear" model that shrunk the earcups, reducing their noise-blocking ability, and adding a $50 rechargeable battery that the earphones couldn't function without. Now there's QuietComfort 15 ($300), a direct and cosmetically almost identical replacement for the QuietComfort 2, making another round of iterative changes without fixing one of the core issues with its predecessors.

As with QuietComfort 2, QuietComfort 15 is a pair of black and silver, “around-ear” headphones with soft leather and foam padding for the top of your head, as well as your ears, cushioning the plastic surfaces that would otherwise cause the most physical discomfort during extended listening. Black plastic frames are used to hold the earcups in place, and metal is found inside the stems to help QC15 expand to fit larger heads. A single AAA battery powers QC15 for 35 hours, the same as QuietComfort 2, and drains only when you flip a power switch on the right earphone. Bose includes a carrying case, a single 5.5-foot audio cable, an old-fashioned two-prong airline adapter, a single AAA battery, and once again, a set of “courtesy cards” in the package so that you can point fellow travelers in Bose’s direction if you like what you’re hearing.

Notably, most of these components have changed a little from the QC2 and QC3. Bose’s new carrying case remains hard inside but has a soft, spandex-like outer shell, with a flexible rear pocket that could conceivably hold an iPod or similar device. There’s no carrying strap this time; instead, there’s just a small nylon loop at the top. The single audio cable now uses a ray gun-shaped, iPhone- and iPod-compatible headphone plug, and has a two-position integrated switch that can be toggled from the default iPod- and iPhone-ready “hi” position to “lo” for louder devices. Apart from the little cable compatibility boosts, the package feels like a small downgrade from the QC2 and QC3 kits, which also included 5-foot extension cords and adapters for use with 1/8” ports on home stereo amplifiers, both absent here.

Pack-ins aside, there are two dimensions of the QuietComfort 15’s performance that will be of most substantial interest to potential buyers: sound quality and noise cancellation quality relative to less expensive competitors. Starting with sound quality, the way we’d describe QuietComfort 15 is as follows: it’s a nice enough pair of earphones, but in no way special or a standout given the $300 asking price. When we put on any new pair of earphones, we evaluate them from a couple of different perspectives: do they sound great right out of the box? And how do they sound against similar competitors? Out of the box, QC15 struck us as a low-end-skewed pair of earphones, pushing the mid-bass up just a little too much and leaving out treble that we were accustomed to hearing in other headphones. Cymbals sounded a little flat, and music just didn’t sound as dynamic as we had hoped it would through a 2009 update to the QuietComfort line. On an absolute scale, we’d call the sound “good, not great.”

What about alongside competitive options, most importantly Audio-Technica’s excellent ATH-ANC7b, which has an $80 lower MSRP, and actually sells for $100-$150 less than the QuietComfort 15s given that Bose’s equipment is almost never sold at a discount? Sonically, the ATH-ANC7b has a decided advantage in audio performance for the dollar. If both pairs of headphones were $300, they’d be neck-and-neck rivals, as the QuietComfort 15s have more and clearer treble, plus a little more bass, while the ATH-ANC7b are a hint cleaner in the mids and lows, but a little less extended in the bass department. It would be hard to prefer the QC15s by much if at all if the prices were identical, however, at an $80 to $150 difference, there’s no question that the Audio-Technicas deliver far more bang for the buck. That having been said, both the ATH-ANC7b and the QuietComfort 15s handily beat the sound we’ve heard from other low-priced competing options; they’re both using better-tuned speakers than noise-cancellers we’ve tested at $100 and $150 MSRPs.

One other key point weighing in favor of the Audio-Technica option is the fact that it continues to work even when you’re out of battery power—an issue the QuietComforts have continued to have generation after generation. If Bose’s batteries lasted twice as long as Audio-Technica’s, or their performance was markedly better, we might understand this difference, but the ATH-ANC7b’s single AAA is rated for 40 hours of active noise cancellation use versus Bose’s 35. Practically, what this means is that if for whatever reason you drain the battery of the QC15 and aren’t carrying a spare, you can’t listen to your music. Audio-Technica’s design—like most others we’ve seen recently—lets you continue to hear your music, albeit with diminished fidelity and only the passive noise-cancellation of the earcups. That’s better than nothing, and for people who accidentally leave things like iPods and headphones turned on, a reason to either keep spare batteries around or pick headphones that keep working when they’re out of juice.

On the flip side, the QuietComfort 15 does have the edge in active noise-cancellation for as long as its battery lasts. Bose says that it has “significantly improved” QC15’s “noise reduction across a wider range of frequencies,” using new noise-sampling microphones both inside and outside each of the earcups to help figure out and reduce whatever non-music sounds you would otherwise be hearing; it has also redesigned its ear cushions to improve noise seal. Between these changes, there’s no doubt that QC15’s active noise-canceling technology does offer a modest improvement over the sampling technologies used by Audio-Technica and many other companies at this point in time. Though QC15 still doesn’t completely eliminate ambient sounds—we could still, for instance, hear music playing right next to us and airplanes flying immediately overhead when wearing the QC15s and competitors—Bose’s new technology reduces the impact of these sounds by something that sounds like 5-10% by comparison with the ATH-ANC7b, at least, when no music is playing. Play music through both of them and you’ll focus on the sounds of whatever you’re hearing, making the active and passive noise-canceling differences seem relatively minor.

Overall, Bose’s QuietComfort 15 is a good but not great pair of headphones, strongest in its new noise-canceling functionality, solid rather than excellent in sound quality, and somewhat less impressive than its predecessors in pack-ins. We believe that this model deserves praise for its comfort, as it remains soft and easy to wear on ears and heads of varying sizes, but that it has failed to keep up with increasingly impressive competitors from a price-to-performance standpoint. Given that Bose continues to maintain a $300 asking price for these headphones in the face of competition from quite a few good to great recent options that sell for considerably less, we consider these to be worthy of a general rather than a high recommendation; if it was our money to spend, we’d sooner save $100 and go with the Audio-Technica ATH-ANC7b, which delivers a comparatively aggressive bundle of performance and pack-ins for a lower price. That said, if having a small edge on noise cancellation or sonic clarity is important to your needs, QuietComfort 15 is a viable option.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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